Ecosystems

What is an ecosystem?

An ecosystem is defined as a self-sustaining community of organisms
living in a physical environment. Part of what sustains an ecosystem
is the constant interchange of matter between its living and physical
components. This is the focus of Session 8: Material Cycles in Ecosystems.

Coniferous forest, a North
American
ecosystem

Ecosystems can be vast, like the tropical rainforests that occur along
the equator. They can also be very small, like the ecosystem inside the
leaves of pitcher plants discussed by Dr. Aaron Ellison in the video.

An ecosystem is shaped by physical factors such as rainfall, temperature,
humidity, sunlight, and soil type. The interaction of these factors determines
the types of organisms that live there. Scientists classify larger terrestrial
ecosystems into several major types that occur over wide geographical
areas. They are recognized by their distinctive climates and are given
their names from the dominant plant life.

The ecosystems listed below are found in North America, including Hawaii.
Which ecosystem do you live in?

Ecosystem type

Average Precipitation

Average Temperature

Dominant Plant Life

Tropical rain forests

250+ cm
(100+ in.)

20 - 28°C
(68 - 82°F)

Broad-leaved trees; dense undergrowth; more species
than any other ecosystem